Field of the Invention
The present invention relates to a liquid ejection head and a liquid ejection apparatus, and more specifically to a configuration for controlling a temperature of the liquid ejection head.
Description of the Related Art
In a liquid ejection head in which a plurality of liquid ejection openings are provided, a temperature of ink is made even with respect to the respective ejection openings by controlling temperatures of the liquid ejection head. In this way, for example, a variation in the amount of ink ejected from the respective ejection openings is suppressed.
Meanwhile, as described in U.S. Pat. No. 6,955,424, there is a liquid ejection head in which ejection opening rows of different types of ink and individual passages along the respective ejection opening rows are formed in one print element board included in the liquid ejection head. In this configuration, liquid is supplied to respective ejection openings of the corresponding ejection opening rows from the respective passages. In this way, a size of the print element board may be set to be small when the liquid ejection head for a plurality of types of ink is configured. As a result, it is possible to achieve miniaturization of the liquid ejection head and a cost reduction.
In a liquid ejection head, a print element board and liquid inside the passage provided in the board tend to increase in temperature due to driving of a heating element associated with ejection of liquid. Meanwhile, liquid newly flowing into the passage of the print element board is relatively lower in temperature than the print element board, and functions to decreases a temperature of the print element board.
Herein, in the print element board described in U.S. Pat. No. 6,955,424, a plurality of openings for guiding liquid to the passage along the ejection opening row are arranged in a direction in which the passage extends. For this reason, a temperature difference occurs between liquid ejected from an ejection opening around the opening and liquid ejected from an ejection opening in a region separated from the opening due to liquid, a temperature of which is relatively low, flowing into the openings. As a result, a temperature distribution may be generated in liquid ejected from the plurality of ejection openings in the ejection opening rows, and the amount of ejected liquid may vary.